Days

From the remotest time to the present the Israelites have computed the day (yôm) from sunset to sunset, or rather from sunset to the appearance of the first three stars which marked the beginning of a new day [Cf. Lev. 23:32; II Esd. (Nehem.) 4:21; etc.]. Before the Babylonian Exile the time between sunrise and sunset was divided into "morning", "midday", and "evening" (Psalm 54:18; Hebrew 55:17); but during the stay in Babylon the Hebrews adopted the division into twelve hours (Cf. John 11:9), whose duration varied with the length of the day. On an average, the first hour corresponded to about 6 a.m.; the third hour to 9 a.m.; the end of the sixth to noon; while at the eleventh the day was near its close. Earlier than this division of the day by hours was that of the night into three watches: the first till midnight; the second or middle watch (cock-crow) till 3 a.m.; and the third or morning watch till about 6 a.m.

Weeks

Seven consecutive days form the week, or second element of the Jewish calendar. As in our ecclesiastical calendar, the days of the Jewish week are numbered, not named. They are called the first day, the second day, the third day, and so on to the seventh, which last is also called "sabbath" (shábbath) a name likewise used to designate the week itself. The sixth day, our Friday, is also known in the New Testament, in Josephus, and in Rabbinical writings as "the eve of the sabbath", or as "the day of the preparation", the paraskeué, a term still employed by the Latin Church in connection with Good Fridays (Cf. Mark 15:42; Josephus, Antiquities of the Jews, XVI, 6:2; Talmud of Jerusalem, Treatise Pesahîm, chap. 4:I).

Months

The third and most important element in the Jewish arrangement of time is the month. The two Hebrew words for month are yéráh, and hodésh, whose primitive meaning, "moon", "new moon", points to the dependence of the Jewish month on the phases of the moon. As a matter of fact, the Hebrew months have always been lunar, and extended from one new moon to another. The beginning of the month with the appearance of the new moon was--as it is still--of great practical importance among the Hebrews, inasmuch as the first of every month was to be observed as New Moon's Day, and certain feasts were affixed to the 10th, 14th, or other days of the month. The earliest appearance of the new moon was long ascertained by direct observation, and authoritatively settled by a commission of the Sanhedrin, and the intelligence then made known to the Jews at large, first by means of fire signals, and later on through special messengers. In the present day, and for many centuries, this very primitive manner of fixing the beginning of the month has given way to a systematic calculation of the latter's duration, and the Jewish calendar is now constructed on the basis of a mean lunation of 29 days, 12 hours, 44 min., and 30 sec. Besides being indicated by means of numerals, the first month, the second month, etc., the Hebrew months have been designated in the course of Jewish history by two sets of names. Of the former set--going back probably to Chanaanite times--only four names have survived in the Hebrew Bible. These are: 'Abhîbh (A.V.Exodus 13:4, 23:15; Deuteronomy 16:1), subsequently the first month; Zíw (1 Kings 6:1), subsequently the second month; 'Ethanîm (1 Kings 8:2), subsequently the seventh month; and Bûl (1 Kings 6:38), subsequently the eighth month. The latter set of names, certainly of Babylonian origin, began to be used after the Exile. Of its twelve names now found in the Jewish calendar only seven occur in the Hebrew text, but the whole twelve appear as the main divisions of the Megillath Ta'anith (Scroll of Fasting), which in its original form is referred to a date before the Christian Era. These twelve names are as follows:

Years

The twelve months thus named made up the ordinary year (shanah), or next important element in the Jewish calendar. As they were lunar months they formed a mean year of 354 days, a year consequently shorter than the solar year by ten or eleven days. This difference, as can be readily seen, would have, in the course of time, completely disordered the months in relation to the seasons of the year; thus the first month, or Nîsan, (corresponding to the end of March or the beginning of April), in the middle of which the first ripe barley was to be presented to Yahweh in connection with the paschal feast (Exodus 12:1 sqq., 13:3 sqq; Leviticus 23:10-12), might have fallen in the middle of winter; and some other festivals depending likewise on the products of the seasons would also have been materially interfered with. Hence it was soon felt--how soon cannot now be ascertained--that the difference between the lunar and the solar years should be equalized by the intercalation of a month. The year in which such an intercalation should be made was for a while determined by an authoritative decision of the Sanhedrin, and ultimately fixed in a permanent manner by astronomical calculation. In a cycle of nineteen years the third, sixth, eighth, eleventh, fourteenth, seventeenth, and nineteenth are made leap-years with an average length of 384 days, by the addition of a month following the twelfth ('Adar), and usually called We-'Adar (Second Adar). It is plain, therefore, that the Jewish year has long been, and still is, a luni-solar year. The Hebrew year thus far described is one constituted in harmony with ritual requirements, and hence it is called the sacred Jewish year. Together with it the Jews have had from time immemorial what may be called a common or civil year commencing in the month of Tíshrî (corresponding generally to part of September and part of October), on or immediately after the new moon following the autumnal equinox. The beginning of the Hebrew civil year practically coincides with that of seed time in Palestine, while the beginning of the sacred year corresponds to that of the harvest season in the same country.

Eras

There now remains to consider the era, or last element of the Jewish calendar. As might well be expected in connection with a people whose history has been so checkered, the Hebrews have adopted various points of time from which to reckon the succession of years. Their principal ancient eras have been:

For centuries they have employed their present method of counting by anno mundi (A.M.). (See the table below for the yearly arrangement of the principal festival days.)

According to the current Jewish reckoning the calendar is dated from the Creation of the World, which is considered to have taken place 3760 years and 3 months before the commencement of the Christian Era. To find the number of the Hebrew year, beginning in the autumn of a given year of our common era, we have to add 3761 to the number of the latter. Thus the Jewish year beginning September, 1908, is 5669 A.M.

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